Method for the treatment of textile fibres

ABSTRACT

This specification discloses a method of crimping protein fibres by drafting. Untwisted fibres are treated with an aqueous solution of alcohol, which may optionally contain an acid and a setting agent for the protein fibres, such as formaldehyde. They are then drafted and are subsequently relaxed to form the crimps. The crimps can be set, for example by steam, with the help of the setting agent after processing and the fibres dried. The preferred alcohol and acids are those which will evaporate on drying, notably having boiling points below 120*C. The drafted fibres may be set without applied tension, and the resulting crimp waves set as mentioned above. Alternatively the drafted fibres may be set in tension and the fibres relaxed at a later stage to produce the crimps. They can be relaxed, for example, after conversion into yarn or fabric. The invention also provides apparatus in which the method can be carried out, a preferred feature being the use of a vacuum padding device which causes rapid and complete wetting of the fibres with the alcohol solution. The invention overcomes the disadvantages inherent in crimping conduct by drafting twisted fibres.

llmehara et al. 8 g

METHOD FOR THE TREATMENT or TEXTILE FIBRES [75] Inventors: Ryo Umehara;Fujio Bekku, both of lchinomiya, Japan I [73] Assignee: I.W.S. NomineeCompany Limited,

London, England [22] Filed: May 16, 1972 [21] Appl. No.: 253,797

30 Foreign Application Priority Data May 20, 1971 Japan..."v 46-83636us. 01. 28/7217, 8/128 A, 28/75'WT Int. Cl. D02g 3/36, D02j 1/22 Fieldof Search 28/721, 75 WT, 76 R, 7217;

19/66 R; 8/127.6, 128 R, 128 A References Cited UNITED STATES PATENTS3,677,694 7/1972 Sugimoto et al 8/128 A 3,687,605 8/1972 Farmer 8/128 AFOREIGN PATENTS OR APPLICATIONS 3/1965 Great Britain 28/7217 PrimaryExaminerLouis K. Rimrodt Attorney, Agent, or Firm-Harold L. Stowell 451Nov. 26, 1974 [57 ABSTRACT This specification discloses a method ofcrimping protein fibres by drafting. Untwisted fibres'are treated withan aqueous solution of alcohol, which may optionally contain an acid anda setting agent for the protein fibres, such as formaldehyde. They arethen drafted and are subsequently relaxed to form the crimps. The crimpscan be set, for example by steam, with the help of the setting agentafter processing and the fibres dried. The preferred alcohol and acidsare those which will evaporate on drying, notably having boiling pointsbelow 120C. The drafted fibres may be set without applied tension, andthe resulting crimp waves set as mentioned above. Alternatively thedrafted fibres may be set in tension and the fibres relaxed at a laterstage to produce the crimps. They can be relaxed, for example, afterconversion into yarn or fabric. The invention also provides apparatus inwhich the method can be carried out, a preferred feature being the useof a vacuum padding device which causes rapid and complete wetting ofthe fibres with the alcohol solution. The invention overcomes the disadvantages inherent in crimping conduct by drafting twisted fibres.

21 Claims, 3 Drawing Figures I l I 4144-42 METHOD FOR THE TREATMENT orTEXTILE FIBRES This invention relates to a method and apparatus fordrafting non-twisted protein fibres to crimp them spontaneously.

Keratin fibres can be crimped in the form of top or carded sliver by astuffer box method, in the form of top or yarn by thetwist-draft-set-untwist method and in the form of yarn by thedraft-release method.

In fibres crimped by the stuffer box method the curvature at certainpositions in the crimped fibres is exceedingly sharp, and strain isconcentrated in these I sharply curved portions. As the fibres are steamset in such a configuration, the tensile strength of the fibres isgreatly reduced. Steam-setting produces only a temporary set and whenpermanent set is required, chemical setting with inorganic or organicreducing agents is employed. Permanent setting further reduces thetensile strength and this causes problems in subsequent processing or inthe quality of thefinal product.

In the twist-draft-set-untwist method and the draft- I release method,the fibres are drafted mechanically and sults.

As highly drafted fibres are not the stable a-type keratin fibres ofnatural wool, the fibres are severely damaged. When subjected to settingwith boiling water, steam or chemical agents for permanently setting thecrimp, the fibres are further damaged, and the tensile strength isfurther reduced. In methods involving twisting the fibres as describedabove, it becomes very difficult to dry them and it is uneconomical tountwist them.

A first aspect of the present invention relates to a method for crimpingprotein fibres by applying to the fibres anaqueous solution of analcohol, drafting the fibres, and subsequently relaxing the fibres.

Non-twisted keratin fibres are preferably used in this invention.Keratin fibres include sheeps wool, mohair, alpaca, vicuna, llama,cashmere, and camel hair, and may be used in the form of carded sliver,tops and rovings of such fibres, which are non-twisted and arrangeduniformly parallel along the fibre axis.

In the preferred practice of the invention, the fibres are wellimpregnated in an acid-containing or alkalicontaining aqueous solutionof an alcohol, which generally contains a high concentration of thealcohol, in

"order to render them draftable more readily and with a reduced energy.Keratin fibres are characterised by a 30 percent index; that is to saythat when sheeps wool is drafted by 30 percent and then released, itrecovers to the original state without any internal strain. The treatedfibre when adequately dried shows the same tensile strength propertiesas untreated sheeps wool fibres. While the performance of the inventiondoes not depend upon any theory as to its mode of operation, thisphenomenon is understood to be due to the opening by water of thehydrogen bonds stabilising the polypeptide chain, which can be reversedon drymonoethanolamine sulphite, monothanolamine bisuling. Additionallythere are other reversible bonds having the propertyof stabilising thepolypeptide chain, such as salt bonds and hydrophobic bonds. The formerbond is opened by adding acid or alkali and the latter bond is opened byan alcohol. Thus the drafting properties of'sheeps wool and otherkeratin fibres can be further increased.

The impregnating media consisting of an acidcontaining oralkali-containing aqueous solution of an alcohol should be removed inthe subsequent drying process. If it is not removed substantiallycompletely in the drying process it greatly reduces the strength of thefibres. The acids, alkalis and alcohols which are preferred are thosehaving a similar volatility to water and preferably not having a boilingpoint higher than about 120C. For the purposes of this invention, formicacid (b.p. 100.5C) and acetic acid (b.p. 118C) are the most preferredacids, ammonia (b.p. -33.35C) the preferred alkali, and methanol (b.p.647C), ethanol (b.p. 783C), n-propanol (b.p. 972C), iso-propanol (b.p.825C), n-butanol (b.p. 1 177C) and iso-butanol (b.p. 108C) are thepreferable alcohols, especially npropanol and iso-propanol. The acid oralkali is added in such an amount as to make the pH of the aqueoussolution strongly acidic or strongly alkaline. The concentration of thealcohol in water is normally at least 10 percent by volume and ispreferably in the range 10-50 percent by volume.

Y Keratin fibres themselves are hydrophobic and if they are impregnatedunevenly, the subsequent treatment is adversely affected. As the fibresshould be impregnated evenly and rapidly it is desirable to replace theair surrounding the fibres quickly and completely by the impregnatingliquid described above or its vapour. It is also desirable to allow thefibres to stand for a time after removal from the impregnating liquid toallow penetration of the impregnating liquor. Unless the fibres areallowed to stand for a sufficient time, they will subsequently bedrafted unevenly and it will be difficult to obtain effective crimping.

The fibres treated in accordance with the invention do not have anytwist and absorb the liquid much better than twisted fibres. Subsequentdrying can be quickly performed, and untwisting is not required. Thus,processing becomes simplified. It is recommended to add simultaneously asmall amount of thioglycollic acid,

phite or thiourea dioxide as a setting agent and formaldehyde (formalin,b.p. 96C) as a cross-linking agent for crimp waves produced in asubsequent stage.

The length and the amountof drafting are determined in accordance withthe subsequent crimping are applied (grasped length) and the amount ofdrafting of the fibres. When drafting witha grasped length shorter thanthe length of the individual fibres, the tension on the fibres increasesand when the grasped length is longer than the individual fibres, theamount of fibre slippage increases. When a high tension is applied, finecrimp waves are produced, and when the amount of fibre slippage isgreater, so that a lesser tension is applied, large crimp waves areproduced. Consequently, for obtaining optimum crimp waves, it ispreferable to extend the fibres during drafting by 10 30 percent, and toapply drafting forces to the fibres at at least two points spaced apartby about the average fibre length.

When fibres are drafted and temporarily set under tension, and whenafter spinning the temporary set is removed to produce crimp, it is notrecommended to draft highly. When highly drafted fibres are relaxed inthe form of yarn, stress concentrates at points where the yarn twist isirregular and produces local hardness in the yarn. In such a case,therefore, it is preferable for the grasped length to equal the averagefibre length and to draft moderately, i.e. by 20 percent.

The keratin fibres thus drafted are then set. When they are set withoutany applied tension, stress release rather than dimensional change isproduced, but when they are set under tension, a dimensional change andnot a stress release is produced. The results are opposite to each otherand the setting conditions can be selected to produce the desiredresult.

When setting without tension (direct crimping method), fibres highlydrafted by 30 percent as described above are released from tension toproduce crimp waves, which can be set by steaming or boiling water,followed by drying to evaporate completely the previously absorbedliquid, When adding a setting agent, for example formaldehyde, linkagesare introduced into the polypeptides to stabilize the molecular chains,and thus the crimp waves are fixed and set.

When being set under tension, (indirect crimping method) keratin fibresdrafted moderately, i.e. by 5 percent as described above, can be steamedand dried under tension to evaporate the impregnating liquid and are settemporarily in the extended state. They can then be spun into yarn in aconventional manner and the fibres are relaxed when in the form of spunyarns or textile material made therefrom: that is, crimps are producedby treatment with steam, hot water or an impregnating liquid asdescn'bedabove. On drying to evaporate water of an impregnating solution themolecular chains again become stabilized, and there are obtained bulkyyarns or textiles.

In the wool industry, fibres are usually allowed to stand for a longtime for top ageing, and this represents a problem in the field. In theindirect crimping method, the period required for top ageing can begreatly shortened to produce end products having an attractive handle.If it is only desired to speed up top ageing the amount of draftingshould be selected to be just'enough to remove the natural crimp wavesof the fibre, preferably less than about 10 percent. In this method, thedrawing process can be performed quickly and continuously and the methodis very advantageous.

The invention further provides an apparatus suitable for carrying outthe method described above, which comprises means for impregnating thefibres with an aqueous solution of an alcohol, preferably containing atleast 10 percent by volume of the alcohol, means for storing theimpregnated fibres to allow penetration of the solution, means fordrafting the fibres and means for setting and drying the fibres. Themeans for impregnating the fibres may be a conventional pad mangle orpreferably a vacuum pad mangle. The drafting means can comprise at leasttwo pairs of nip rollers, at least the second pair being driven at asurface speed faster than the first pair. If there are three pairs ofnip rollers, the third pair can be driven at the same surface speed asthe second pair, whereby drafting forces imposed on the fibres betweenthe first and second pair of rollers are retained between the second andthird pair or, alternatively, the third pair can be driven at a lowersurface speed whereby the drafting forces are released and crimps formin the fibres. The apparatus can further comprise a crimping chamber, adrying chamber provided with means for forwarding the fibres, forexample a pair of belts which in one position can co-operate andmaintain the drafting forces on the fibres, and a cooling device.

One example of the apparatus is shown in the attached drawings and themethod and the apparatus of this invention will be more particularlydescribed hereinafter with reference to the drawings, in which:

FIG. 1 shows a preferred device for completely impregnating or wettingkeratin fibres in or by an impregnating liquid.

FIG. 2 shows apparatus for carrying out the process of this inventionand incorporates the device of FIG. 1.

FIG. 3 is a photographic showing of crimped Australian merino wool asset forth in Example 1.

The device A shown in the drawings may be termed a vacuum padder and iscomposed of rollers 1 to 6 arranged to form a hexagonal section. Two ofthe rollers 2 and 5 are smaller than the others. At either end of thesix assembled rollers pressure plates 7 and 8 are attached to form aclosed space 9 on the inside.

Small rollers 10, 11, 12 and 13 are arranged in pairs above and belowthe main roller assembly. Endless mesh belts 14 and 15 span round therollers l, 2 and 3 and the small rollers 10 and 12 on the left hand sideand around the rollers 4, 5 and 6 and the small rollers 11 and 13 in theright hand side of the drawing respectively. The belts introduce keratinfibres W to be processed and prevent them from winding into the rollers.

A liquid-supplying and discharging device and an exhaustion device arearranged outside the rollers. A tank 16 of an impregnating liquid, isconnected with a closed tank 19 by way of a control cock l7 and a pipe18. A flexible pipe 20 and a flexible pipe 21 are disposed between thepipe 18 and the lower part of the closed space 9 and between the closedtank 19 and the upper part of the closed space, respectively. To theroot of the 'pipe 21, an exhaustion pipe 22 is attached, and isconnected with a vacuum pump. A cock 23 is disposed under the closedtank 19.

In operation, an impregnating liquid is introduced into the tank 16, atwhich time the cocks 17 and 23 are shut. Then the cock 17 is opened tointroduce the liquid through the pipes 18 and 20 into the lower part ofthe closed space 9 to fill it, as shown at 24. The liquid is alsointroduced to the closed tank 19. The air is exhausted from the pipe 22to reduce the pressure in the closed space 9, which becomes saturatedwith vapour of the liquid. The liquid is an acidor alkali-containingaqueous solution containing lO-50 percent by volume alcohol; its pH isadjusted to L0 4.0 or 9.0 l 1.0, and 0.5 5.0 percent formalin andthioglycollic acid, monoethanolamine sulphite or bisulphite, or thioureadioxide may be added.

Non-twisted keratin fibres W are introduced from the upper side into theclosed space 9 by the two endless mesh belts 14 and 15, and passdownwardly through the impregnating liquid 24 retained in thenip betweenrollers 1 and 6. The closed space 9 is kept under reducedpressure (aboutl00-760 mm Hg) by the pressure-reducing means described above. In thespace above the liquid the air in the interstices between the fibres isquickly replaced by the vapour saturated with the impregnating liquid,and then the fibre is padded in the liquid. By this means the keratinfibres can be quickly and uniformly wetted. The fibres are passedbetween the rollers l and 6 to be squeezed to 50 100 percent wet pickup.

In the apparatus of FIG. 2, a U-type duct storage chamber B ispositioned under the vacuum padder A, and there are further provided adrafting chamber C, a steaming chamber D, a drying chamber E and acooler F. The drafting chamber, the steaming chamber and the dryingchamber form a single assembly packed in a closed unit 26, divided bywalls 25 and 25. The keratin fibres W which have been passed through thepadder A to improve their drafting properties are passed throughthe'storage duct B and the chambers C, D and E and finally pass over thecooler F.

The inlet arm of the U-type storage duct B is positioned under thepadder, and the outlet arm is under the drafting chamber C. In thehorizontal part of the duct B, two rollers 27 and.28 are provided and anendless mesh belt 29 spans them. The outer wall 30 of the duct isdouble, and the inside of the double wall is maintained at 20 25C bypassing cooling water through pipes 31 and 32 and is closed tightly fromthe ambient air.

In the drafting chamber C, the fibre bundle W passes upwardly overforwarding rollers 33, 34 and 35, which control the applied loadingtension, and then passes over rollers 36 and 37 which are disposedhorizontally. Three co-operating pairs of grip rollers 38, 39 and 40,are arranged horizontally for drafting the fibres and their distanceapart and the surface speed rate can be adjusted to any suitable value.

In the subsequent steaming chamber D, an endless mesh belt 44 passesover rollers 41, 42 and 43 so as to forward the fibres W at the samelevel as that in the drafting chamber. Above the rollers, a little apartfrom them, an endless mesh belt 48 similarly passes over rollers 45, 46and 47 and the distance of the assembly from the lower roller isadjustable. In carrying out the direct crimping method, the latter beltand the rollers are positioned as shown by solid lines, and for theindirect crimping method they are lowered to the position shown bybroken lines so as to maintain the tension on the fibres, and the fibresare given tension by both endless belts 44 and 48. A plurality of smallrollers are provided over which the belts 44 and 48 pass so as to betensioned satisfactorily. A steam jet is directed against the fibrespassing over the belt 44 by means of a pipe 50 provided with many jetholes disposed adjacent to the spaces between the rollers 41, 42 and 43.A pipe 51 is additionally positioned under the chamber through whichsteam can be introduced from an external source to keep the temperaturein the chamber D in the range 80 125C.

, The subsequent drying chamber E is similar to the setting chamber D.In the drawing, the parts similar to those in the chamber D are shown bythe same numerals with an added prime. The steam jet pipe 50 is omitted.The chamber is kept at a temperature in the range of 1l0C.

The chambersare divided by walls 25, 25' and 26, and enclosed by theouter wall. The fibres are passed through the chambers by way of holesprovided in the walls 25, 25 and 26. In the setting chamber D and thedrying chamber E, holes 52 and 53 communicating with a conventionalsolvent-removal device are provided in the upper parts, and ventilationholes 54, 55 and 56 and 57 are provided in the bottom of the draftingchamber, the steaming chamber and the drying chamber and the upper partof the wall between the drafting chamber and the steaming chamber.

A cooler F having a funnel-like section is positioned after the dryingchamber E. It is provided with an end less belt 60 passing over rollers58 and 59, and the fibres W passing over the belt 60 are cooled by airdrawn through the belt by a suction pipe 61, and are then introducedinto a can by a pair of forwarding rollers 62.

In the indirect crimping method the treated fibres are further processedby conventional methods and pass to spinning apparatus and dyeing andfinishing apparatus, and can optionally be knitted into a fabric using aconventional knitting machine. As a device for stress releasing the.fibres in yarn form there may be used a conventional hank washingmachine, hank dyeing machine or a steam box. For knitted fabrics aconventional paddle dyeing machine, a Hofmann press or a winch dyeingmachine can be used.

Keratin fibres can be impregnated rapidly and uniformly with animpregnating liquid in the vacuum padder A illustrated in FIG. 1 andthen pass to the U-type storage duct B in FIG. 2, in which they areallowed to stand for 5 10 minutes to allow penetration of the liquidinto the fibres.

The fibres are passed to the drafting chamber C by way of the tensionadjusting rollers 33, 34 and 35, and are forwarded to the pair of griprollers 38 and 39. The spacing of the grip rollers is adjusted,depending on the average length of fibres to be treated, and the rate ofsurface speed of the pair of grip rollers 39 is controlled to be 1.0 1.3times as fast as that of the pair of rollers 38, so as to draft thefibres. The rate and the amount of drafting depend on the treatingmethod to be employed later, as described previously. In the directcrimping method, the surface speed of the rollers 40 is adjusted to bethe same as that of the rollers 38 so that the fibres are overfed by therollers 39 and become crimped. The fibres are then forwarded to thesteaming chamber D and remain for 30 60 seconds under no appliedtension. A steam jet is directed from the pipe 50 against the fibresthrough the mesh belt 44 to evaporate the impregnating liquid and setthe fibres at 80 125C. The evaporated impregnating liquid is dischargedout of the exhaust hole 52 to a collector and there collected forre-use. The fibres are then introduced into the drying chamber, whereinthey are dried under no applied tension for 30 60 seconds at 80 C toevaporate completely the remaining volatile impregnating liquid. Then,thefibres are forwarded to the cooler F to be cooled.

In the indirect crimping method, the endless mesh belts 48 and 48'positioned above the rollers in the steaming set chamber D and thedrying chamber E are both lowered to co-operate with the lower endlessbelts 44 and 44', so as to maintain drafting forces on the fibres in thedrafting chamber. The fibres are drafted with a small amount ofdrafting, usually 20 percent but more especially less than percent byadjusting each pair of rollers and the fibres remain under tension whilepassing through the steaming chamber D and the drying chamber E. Thefibres passing through between the endless belts 44 and 48 are contactedwith steam from steam jets 50 in the steam setting chamber D for 30 60seconds, to evaporate the volatile impregnating liquid and temporarilyset the fibres at 80 125C. Then they are dried in the drying chamber Eat 80 110C for 30 60 seconds, also under tension, to complete theevaporation of the volatile liquid and .this is followed by cooling bythe cooler F.

The fibres can subsequently be sent to a gill and then spun into yarnson a conventional spinning machine. Yarns or textile fabrics producedfrom the yarns can be treated in dyeing and finishing apparatus usingsteam or boiling water as a medium, for 30 60 seconds in the case ofyarns and for 10 minutes in the case of textile fabrics. Then, they canbe dried and cooled to produce crimps and bulked spun yarns or textilesobtained having a good handle. If necessary they may be treated with theimpregnating liquid described above after the above-described treatment.

The invention is further illustrated by the following Examples.

EXAMPLE 1 50% by volume 47% 3% water n-propanol formaldehyde solution(40%) The top was then squeezed to 84 percent wet pick-up by the vacuumpadder and allowed to stand for 5 minutes at room temperature. It wasdrafted to 30 percent extension at room temperature using a grip rollerspacing of 76 mm, and the tension was released at room temperature toproduce crimp waves. The crimpedtop was then set by steam at 2 kg/cmpressure, while maintaining an ambient temperature of 120C, for 30seconds without applied tension and dried with an indirect heater at105C for 60 seconds without applied tension. The crimped fibresexhibited 7 crimps/4 cm as shown in FIG. 3. The top treated by the abovecrimping method was wound round a glass bar and exposed to boiling waterfor 10 minutes, but crimp waves still remained.

EXAMPLE 2 By the same treatment as described in Example 1, except thatdrafting ratios of 10 percent and 20 percent respectively were used,there were obtained crimp waves of 5 crimps/4 cm fibre and 6 crimps/4cmfibre. The crimped top was wound round a glass bar and treated inboiling water for 10 minutes, but the crimps were not removed by thistreatment.

EXAMPLE 3 The same treatment as described in Example 1 was employed,except that the impregnating solution composition was as follows:

water 50% by volume n-propanol 45% by volume 86% formic acid 571 byvolume pH 2.5

There were obtained 8 crimps/4 cm fibre. The crimped top was treated inboiling water for 10 minutes, and crimp waves of longer frequency,namely 4 crimps/4 cm fibre, were obtained.

EXAMPLE 4 Australian merino 50S wool top of 20 g/m, 3477 1., mean fibrelength, 199.69 mm and oil content 0.60 was immersed in a solution havingthe following composition, squeezed to 80 percent pick-up with a mangleand allowed to stand at room temperature for 5 minutes:

water 5071 by volume n-propanol 4771 do. formaldehyde 3% do.

After the impregnated top had been allowed to stand, it was drafted toan extension of 30 percent with grip roller spacing of about 120 mm,which equalled the mean fibre length, at room temperature. The draftedtop was then quickly released from drafting to produce crimp waves andwas steamed with 2 kg/cm steam, in a chamber maintained by an indirectheater at 120C, for 30 seconds without applied tension to set thefibres, and was then dried at 105C for seconds without applied tension.There were obtained 7 crimps/6 cm fibre. The crimped top was wound rounda glass bar and exposed to boiling water for 10 minutes, but the crimpwaves were not eliminated.

EXAMPLE 5 Australian merino S top of 20 g/m mean fibre length 75.00 mm21.14 1. and oil content 0.26, and having received an anti-shrinkingtreatment with 4.5 percent on the fibre weight of sodiumdichloroisocyanate, was immersed in a solution of the followingcomposition, squeezed to percent pick-up with a pad mangle and allowedto stand at room temperature for 5 minutes:

water 50% by volume n-propanol 47% by volume 86% formic acid 3% byvolume pH 2.5

After being allowed to stand, the top was drafted to 20 percentextension with a grip roller spacing of 75 mm (the mean fibre length)and then relaxedquickly from drafting at room temperature to producecrimp waves. The crimp top was steamed at 3 kg/cm presure for 30 secondsand at a temperature of 125C, maintained by an indirect heater, withoutapplied tension and dried at C for 60 seconds without applied tension.There were obtained 8 crimps/4 cm fibre. The crimped top was treatedwith boiling water for 10 minutes without tension, and crimp waves werenot removed by this treatment.

EXAMPLE 6 Australian merino 64S top of 20 g/m, meanfibre length 75.84 mm2122p. mean fibre diameter and oil content 0.68 was immersed in asolution of the following composition, squeezed with a mangle to 84percent wet pick-up and allowed to stand at room temperature forminutes:

water 50% by. volume n-propanol 47% by volume 86% formic acid 3% byvolume pH 2.5

After being allowed to stand, the top was drafted to percent extensionat room temperature with a grip rol- EXAMPLE 7 By the same treatment asdescribed in Example 1 was employed, except that the impregnatingsolution composition was as follows:

water 50 '74 by volume iso-propanol 49.9% by volume 28% ammonia 0.1% byvolume pH 10.5

There were obtained 10 crimps/4 cm fibre, the crimped top was treatedwith boiled water for 10 minutes, and there were obtained 8 crimps/4 cmfibre.

EXAMPLE 8 By the same treament as described in Example 1 was employed,except that the impregnating solution composition was as follows:

water iso-propanol thioglycollic acid 50% by volume 47% do. 3% do.

There were obtained 8 crimps/4 cm fibre. The crimped top was treatedwith boiled water for 30 minutes and there were obtained 8 crimps/4 cmfibre.

EXAMPLE 9 By the same treatment as described in Example 1 was employed,except that the impregnating solution composition was as follows:

water 50 by volume iso -ypropanol 49.9 by volume 28 o ammonia 0.1 byvolume o.w.f.

thiourea dioxide 3 There were obtained whiter and brighter wool composedof 10 crimps/4cm fibre. The crimped top was treated with boiled waterfor 30 minutes and there were obtained 10 crimps/4 cm fibre.

We claim:

1. A method of crimping protein fibres comprising the steps of: applyingto said fibres an aqueous solution containing at least 10 percent byvolume of an alcohol; drafting said fibres; and releasing-said draftingforces applied to said fibres whereby said fibres become crimped.

2. A method according to claim 1 including the additional steps of:setting the crimps in said crimped fibres; and drying said fibres.

3. A method according to claim 1, wherein said aqueous solution appliedto said fibres additionally comprises an acid.

4. A method according to claim 3, wherein said acid has a boiling pointbelow C.

5. A method according to claim 1, wherein said aqueous solutionadditionally comprises formic or acetic acid.

6. A method according to claim 1, wherein said aqueous solution appliedto said fibres additionally comprises an alkali.

7. A method according to claim 1, wherein said aque ous solutionadditionally comprises ammonia.

8. A method according to claim 1, wherein said alcohol has a boilingpoint below 120C.

9. A method according to claim 1, wherein said alcohol is selected fromthe group consisting of n-propanol and isopropanol.

10. A method according to claim 1, wherein said alcohol is selected fromthe group consisting of methanol, ethanol, n-butanol and isobutanol.

11. A method according to claim 1, wherein said im- 15..A methodaccording to claim 1, wherein said v fibres after impregnation with saidsolution are allowed to stand prior to drafting to allow said solutionto penetrate into said fibres.

16. A method according to claim 1, wherein said fibres are drafted byapplying drafting forces at at least two points spaced apart by theaverage fibre length.

17. A method according to claim 1, wherein said fibres are extendedduring drafting by about 10 30 percent. v

18. A method according to claim 1, wherein said fibres are in a formselected from the group consisting of carded slivers, tops and rovingsin which said fibres are nontwisted and arranged uniformly parallelalong the axis of said fibres. V

19. A method of crimping protein fibres comprising the steps of:applying to said fibres an aqueous solution.

containing at least 10 percent by volume of an alcohol; drafting saidfibres; setting said fibres while maintaining drafting forces on saidfibres; drying said fibres; and subsequently relaxing said fibreswhereby said fibres become crimped.

20. A method according to claim 19, wherein said drafted and set fibresare formed into a yarn and said fibres in said yarn are subsequentlyrelaxed.

21. A method according to claim 19, wherein said drafted and set fibresare formed into a yarn, said yarn is formed into a fabric, and saidfibres in said fabric are subsequently relaxed.

1. A METHOD OF CRIMPING PROTEIN FIBRES COMPRISING THE STEPS OF: APPLYINGTO SAID FIBERS AND AQUEOUS SOLUTION CONTAINING AT LEAST 10 PERCENT BYVOLUME OF AN ALCOHOL; DRAFTING SAID FIBERS; AND RELEASING SAID DRAFTINGFORCES APPLIED TO SAID FIBERS WHEREBY SAID FIBERS BECOME CRIMPED.
 2. Amethod according to claim 1 including the additional steps of: settingthe crimps in said crimped fibres; and drying said fibres.
 3. A methodaccording to claim 1, wherein said aqueous solutioN applied to saidfibres additionally comprises an acid.
 4. A method according to claim 3,wherein said acid has a boiling point below 120*C.
 5. A method accordingto claim 1, wherein said aqueous solution additionally comprises formicor acetic acid.
 6. A method according to claim 1, wherein said aqueoussolution applied to said fibres additionally comprises an alkali.
 7. Amethod according to claim 1, wherein said aqueous solution additionallycomprises ammonia.
 8. A method according to claim 1, wherein saidalcohol has a boiling point below 120*C.
 9. A method according to claim1, wherein said alcohol is selected from the group consisting ofn-propanol and isopropanol.
 10. A method according to claim 1, whereinsaid alcohol is selected from the group consisting of methanol, ethanol,n-butanol and isobutanol.
 11. A method according to claim 1, whereinsaid impregnating solution additionally comprises a setting agent forsaid fibres.
 12. A method according to claim 11, wherein said settingagent is selected from the group consisting of thioglycollic acid,monoethanolamine sulphite and bisulphite and thiourea dioxide.
 13. Amethod according to claim 1, wherein said impregnating solutionadditionally comprises a cross-linking agent for said fibres.
 14. Amethod according to claim 13, wherein said cross-linking agent comprisesformaldehyde.
 15. A method according to claim 1, wherein said fibresafter impregnation with said solution are allowed to stand prior todrafting to allow said solution to penetrate into said fibres.
 16. Amethod according to claim 1, wherein said fibres are drafted by applyingdrafting forces at at least two points spaced apart by the average fibrelength.
 17. A method according to claim 1, wherein said fibres areextended during drafting by about 10 - 30 percent.
 18. A methodaccording to claim 1, wherein said fibres are in a form selected fromthe group consisting of carded slivers, tops and rovings in which saidfibres are nontwisted and arranged uniformly parallel along the axis ofsaid fibres.
 19. A method of crimping protein fibres comprising thesteps of: applying to said fibres an aqueous solution containing atleast 10 percent by volume of an alcohol; drafting said fibres; settingsaid fibres while maintaining drafting forces on said fibres; dryingsaid fibres; and subsequently relaxing said fibres whereby said fibresbecome crimped.
 20. A method according to claim 19, wherein said draftedand set fibres are formed into a yarn and said fibres in said yarn aresubsequently relaxed.
 21. A method according to claim 19, wherein saiddrafted and set fibres are formed into a yarn, said yarn is formed intoa fabric, and said fibres in said fabric are subsequently relaxed.